Method for manufacturing a gas phase chromatography column and column obtained using such a method

Abstract

The present invention relates to a method for manufacturing a chromatography column, in particular for a gas phase chromatography, comprising a stationary phase made from a sol. This method comprises the following steps: (a) introducing this sol at the first end of the column, (b) moving said sol towards the second end of the column, so that a sol layer is formed on the internal wall of the column, this layer being able to form a gel on said internal wall, and (c) drying of the gel. The present invention also relates to a capillary column as well as to a microcolumn which may be manufactured according to this method.

The invention claimed is: 
     
       1. A method for manufacturing a chromatography column comprising a stationary phase made from a sol comprising a pore-forming agent, comprising:
 (a) introducing a sol comprising a pore-forming agent at a first end of the column, 
 (b) moving said sol towards a second end of the column, so that a thin sol layer is formed on the internal wall of the column wherein said sol layer forms a gel on the internal wall of the column, 
 (c) drying the gel, and 
 (d) removing the pore-forming agent from the dried layer, so as to form a microporous, mesoporous layer or other porous layer, the size and/or the density of the pores being controlled, said porous layer forming the stationary phase. 
 
     
     
       2. The method according to  claim 1 , wherein the sol forms a plug, extending from the first end of the column and over a length of less than two-thirds of the total length of the column, the plug being moved along the column under the effect of a pressure. 
     
     
       3. The method according to  claim 1 , wherein (c) is carried out by circulating a gas inside the column and, if required, during (a). 
     
     
       4. The method according to  claim 3 , wherein the gas is air or helium, nitrogen or another inert gas. 
     
     
       5. The method according to  claim 1 , wherein the pore-forming agent comprises cetyltrimethylammonium bromide (CTAB), diblock copolymers of ethylene oxide and of propylene oxide, triblock copolymers of ethylene oxide and of propylene oxide, or another surfactant. 
     
     
       6. The method according to  claim 1 , wherein (d) is carried out after (c) with a treatment selected from the group consisting of calcination, washing with an organic solvent of the alcohol or acetone type, and UV insolation. 
     
     
       7. The method according to  claim 6 , wherein the calcination is carried out by circulating dry oxygen, dry helium, dry nitrogen or another dry gas inside the column, the temperature of this gas being comprised between 100° C. and 500° C. 
     
     
       8. The method according to  claim 1 , wherein (a) to (c) are reproduced at least once before applying (d). 
     
     
       9. The method according to  claim 1 , wherein further comprising subjecting the internal wall of the column to a preparation treatment prior to (a) to reinforce the adhesion of the sol on the internal wall, wherein said treatment increases the hydrophilicity of the internal wall. 
     
     
       10. The method according to  claim 1 , further comprising subjecting the internal wall of the column to an activation treatment prior to (a) to reinforce adhesion of the stationary phase, wherein the activation treatment promotes covalent grafting between the gel and the internal wall during the condensation of the gel. 
     
     
       11. The method according to  claim 10 , wherein the activation treatment of the internal wall of the column is carried out by oxidation of said internal wall, this oxidation being carried out by plasma, via a gas route or via a liquid route. 
     
     
       12. The method according to  claim 1 , wherein the internal wall of the column is in silicon, in silica, in molten silica, in polymer or in metal. 
     
     
       13. The method according to  claim 1 , wherein the stationary phase has a thickness of less than or equal to 3 μm. 
     
     
       14. The method according to  claim 1 , wherein the chromatography column is a capillary column with an internal diameter of less than or equal to 2 mm. 
     
     
       15. The method according to  claim 1 , wherein the chromatography column is a microcolumn for which at least one of the internal transverse lengths is less than or equal to 500 μm. 
     
     
       16. The method according to  claim 1 , wherein:
 the sol forms a plug, and 
 (b) comprises moving the plug along the column. 
 
     
     
       17. The method according to  claim 16 , wherein moving the plug forms the thin layer of the sol on the internal wall of the column. 
     
     
       18. The method according to  claim 16 , comprising moving the plug under the effect of pressure. 
     
     
       19. The method according to  claim 16 , comprising forming the plug to have a length of 20 to 50 cm in the column. 
     
     
       20. The method according to  claim 16 , comprising selecting a moving speed of the plug to leave the thin layer of the sol having a desired thickness on the internal wall of the column. 
     
     
       21. The method according to  claim 16 , comprising selecting a solvent concentration of the sol to leave the thin layer of the sol having a desired thickness on the internal wall of the column. 
     
     
       22. The method according to  claim 16 , comprising selecting a volume of the sol to form the plug to leave the thin layer of the sol having a desired thickness on the internal wall of the column. 
     
     
       23. The method according to  claim 16 , comprising forming the plug to extend over a length less than two thirds of a length of the column. 
     
     
       24. The method according to  claim 16 , comprising forming the plug to extend over a length less than half of a length of the column. 
     
     
       25. The method according to  claim 16 , comprising forming the plug to extend over a length less than one third of a length of the column. 
     
     
       26. The method according to  claim 16 , comprising forming the plug to extend over a length less than one tenth of a length of the column. 
     
     
       27. The method according to  claim 16 , comprising forming the plug to extend from the first end over a length less than a length of the column. 
     
     
       28. The method according to  claim 1 , wherein:
 the sol forms a plug at the first end, and 
 (b) comprises moving the plug from the first end to the second end. 
 
     
     
       29. The method according to  claim 28 , comprising moving the plug under the effect of pressure. 
     
     
       30. The method according to  claim 1 , comprising:
 moving said sol towards a second end of the column to form the thin sol layer on the internal wall of the column and a passage from the first end to the second end. 
 
     
     
       31. The method according to  claim 30 , comprising:
 flowing a gas through the passage to dry to sol layer. 
 
     
     
       32. The method according to  claim 2 , comprising moving the plug under the effect of pressure of a gas or of a supercritical fluid. 
     
     
       33. The method according to  claim 32 , wherein the gas is the same as a gas applied in (c).